Wireless communication system, relay station apparatus, and wireless communication method

Abstract

A wireless communication system includes a base station apparatus, a mobile station apparatus that performs wireless communication with the base station apparatus, and a relay station apparatus that relays wireless communication between the base station apparatus and the mobile station apparatus. The relay station apparatus switches between transmitting and not transmitting a synchronization signal or a reference signal to be transmitted to the mobile station apparatus.

1 . A wireless communication system comprising a base station apparatus, a mobile station apparatus that performs wireless communication with the base station apparatus, and a relay station apparatus that relays wireless communication between the base station apparatus and the mobile station apparatus, wherein
 the relay station apparatus switches between transmitting and not transmitting a synchronization signal or a reference signal to be transmitted to the mobile station apparatus.   
     
     
         2 . The wireless communication system according to  claim 1 , wherein the relay station apparatus has an idle mode, in which the synchronization signal and the reference signal are not transmitted, and an operating mode, in which the synchronization signal and the reference signal are transmitted, and wherein by switching the mode, switching is done between transmission and non-transmission of the synchronization signal and the reference signal. 
     
     
         3 . The wireless communication system according to  claim 2 , wherein, when the relay station apparatus that is in the idle mode receives a paging signal from the base station apparatus, switching is done to the operation mode. 
     
     
         4 . The wireless communication system according to  claim 3 , wherein an equipment identification number that is to allocated to each of the mobile station apparatuses is allocated to the relay station apparatus, and
 the paging signal includes the equipment identification number that is allocated to the relay station apparatus targeted by the paging signal.   
     
     
         5 . The wireless communication system according to  claim 3 , wherein the relay station apparatus intermittently receives the paging signal. 
     
     
         6 . The wireless communication system according to  claim 3 , wherein, when wireless communication is established between the base station apparatus and the mobile station apparatus, based on position registration information received in advance from the relay station apparatus, if the base station apparatus judges that the base station apparatus can communicate with the mobile station apparatus via the relay station apparatus, the paging signal is transmitted to the relay station apparatus. 
     
     
         7 . The wireless communication system according to  claim 1 , wherein the base station apparatus receives position registration information from the relay station apparatus and registers the relay station apparatus into its base station apparatus. 
     
     
         8 . The wireless communication system according to  claim 7 , wherein, upon registration of the relay station apparatus into its base station apparatus, the base station apparatus decides to allocate to the relay station apparatus that has transmitted the position registration information either the same cell identification information as its base station apparatus or separate cell identification information. 
     
     
         9 . The wireless communication system according to  claim 7 , wherein, upon registration of the relay station apparatus to the base station apparatus, the base station apparatus decides cell identification information to be allocated to the relay station apparatus and notifies the relay station apparatus thereof 
     
     
         10 . The wireless communication system according to  claim 1 , wherein, if the relay station apparatus has cell identification information that is different than that of the base station apparatus, the mobile station apparatus receives the reference signal of the relay station apparatus and measures the communication quality with the relay station apparatus; and wherein:
 based on the communication quality measured by the mobile station apparatus, the base station apparatus determines whether or not wireless communication with the mobile station apparatus is performed via the relay station apparatus.   
     
     
         11 . The wireless communication system according to  claim 1 , wherein:
 if the relay station apparatus has a cell identification information that is the same as that of the base station apparatus, the mobile station apparatus receives the reference signal of the relay station apparatus and measures the communication quality with the relay station apparatus, and further receives the reference signal of the base station apparatus and measures the communication quality with the base station apparatus and wherein:   based on the communication quality measured by the mobile station apparatus, the base station apparatus determines whether or not wireless communication with the mobile station apparatus is performed via the relay station apparatus.   
     
     
         12 . A relay station apparatus relaying wireless communication between a base station apparatus and a mobile station apparatus that performs wireless communication with the base station apparatus; wherein:
 the relay station apparatus switches between transmitting and not transmitting a synchronization signal or a reference signal to be transmitted to the mobile station apparatus.   
     
     
         13 . A wireless communication method in a wireless communication system comprising a base station apparatus, a mobile station apparatus that performs wireless communication with the base station apparatus, and a relay station apparatus that relays wireless communication between the base station apparatus and the mobile station apparatus, the wireless communication method comprising:
 switching, by the relay station apparatus, between transmitting and not transmitting a synchronization signal or a reference signal to be transmitted to the mobile station apparatus.